1,1,2,2,3,3,4,4-octafluoro-1,4-diiodobutane

Endpoint summary

Description of key information

A non-GLP screening study by the oral route, 2 dose-range finding studies and a 28-day by inhalation were available in rats and provided partial information but did not allow to determine robust NOAE(C)Ls.

Based on the subacute dose-range finding studies (5 or 7 days) by inhalation, studies showed decreased body weight at 10 ppm and higher, and increased liver and adrenals weights, with effects that were usually more marked in males and at the highest doses. Microscopic examinations showed signs of hepatocellular hypertrophy. In the 7-d DRF, increased ASAT and ALAT, GGT and SDH in males were observed at 291 ppm, as well as increased TSH in males and females at 50.4 ppm and above, consistent with metabolic adaptation. Slight effects on body weight and organ weights were observed in the 28-day inhalation study at the dose of 2 ppm, but were not associated with any microscopic findings.

By the oral route similar effects on body weight, organ weights and swollen liver were observed at the high dose (30 mg/kg/day). No microscopic examination was conducted in this screening study. In addition, a reduced size of testes, epididymides, prostate and seminal vesicles was observed at the high dose. Hormone variations, in particular increased T4 and TSH, were observed especially in the highest dose groups. This was consistent with the inhibition of the 5'-deiodinase activity observed in vitro in rat or human microsomal fractions incubated with diiodoperfluorobutane (reported under specific investigations).

The available set of information was not sufficient to determine a classification.